Ubuntu Manpage: dirmngr - CRL and OCSP daemon

Provided by: dirmngr_2.2.27-3ubuntu2.4_amd64

NAME

       dirmngr - CRL and OCSP daemon

SYNOPSIS

       dirmngr [options] command [args]

DESCRIPTION

       Since  version  2.1  of  GnuPG, dirmngr takes care of accessing the OpenPGP keyservers.  As with previous
       versions it is also used as a server for managing and downloading certificate revocation lists (CRLs) for
       X.509 certificates, downloading X.509 certificates, and providing access to OCSP providers.   Dirmngr  is
       invoked internally by gpg, gpgsm, or via the gpg-connect-agent tool.

COMMANDS

Commands are not distinguished from options except for the fact that only one command is allowed.

--version
Print the program version and licensing information. Note that you cannot abbreviate this
command.

--help, -h
Print a usage message summarizing the most useful command-line options. Note that you cannot
abbreviate this command.

--dump-options
Print a list of all available options and commands. Note that you cannot abbreviate this command.

--server
Run in server mode and wait for commands on the stdin. The default mode is to create a socket and
listen for commands there. This is only used for testing.

--daemon
Run in background daemon mode and listen for commands on a socket. This is the way dirmngr is
started on demand by the other GnuPG components. To force starting dirmngr it is in general best
to use gpgconf --launch dirmngr.

--supervised
Run in the foreground, sending logs to stderr, and listening on file descriptor 3, which must
already be bound to a listening socket. This is useful when running under systemd or other
similar process supervision schemes. This option is not supported on Windows.

--list-crls
List the contents of the CRL cache on stdout. This is probably only useful for debugging purposes.

--load-crl file
This command requires a filename as additional argument, and it will make Dirmngr try to import
the CRL in file into it's cache. Note, that this is only possible if Dirmngr is able to retrieve
the CA's certificate directly by its own means. In general it is better to use gpgsm's --call-
dirmngr loadcrl filename command so that gpgsm can help dirmngr.

--fetch-crl url
This command requires an URL as additional argument, and it will make dirmngr try to retrieve and
import the CRL from that url into it's cache. This is mainly useful for debugging purposes. The
dirmngr-client provides the same feature for a running dirmngr.

--shutdown
This commands shuts down an running instance of Dirmngr. This command has currently no effect.

--flush
This command removes all CRLs from Dirmngr's cache. Client requests will thus trigger reading of
fresh CRLs.

OPTIONS

Note that all long options with the exception of --options and --homedir may also be given in the
configuration file after stripping off the two leading dashes.

--options file
Reads configuration from file instead of from the default per-user configuration file. The
default configuration file is named ‘dirmngr.conf’ and expected in the home directory.

--homedir dir
Set the name of the home directory to dir. This option is only effective when used on the command
line. The default is the directory named ‘.gnupg’ directly below the home directory of the user
unless the environment variable GNUPGHOME has been set in which case its value will be used. Many
kinds of data are stored within this directory.

-v

--verbose
Outputs additional information while running. You can increase the verbosity by giving several
verbose commands to dirmngr, such as -vv.

--log-file file
Append all logging output to file. This is very helpful in seeing what the agent actually does.
Use ‘socket://’ to log to socket.

--debug-level level
Select the debug level for investigating problems. level may be a numeric value or by a keyword:

none No debugging at all. A value of less than 1 may be used instead of the keyword.

basic Some basic debug messages. A value between 1 and 2 may be used instead of the keyword.

advanced
More verbose debug messages. A value between 3 and 5 may be used instead of the keyword.

expert Even more detailed messages. A value between 6 and 8 may be used instead of the keyword.

guru All of the debug messages you can get. A value greater than 8 may be used instead of the
keyword. The creation of hash tracing files is only enabled if the keyword is used.

How these messages are mapped to the actual debugging flags is not specified and may change with newer
releases of this program. They are however carefully selected to best aid in debugging.

--debug flags
Set debugging flags. This option is only useful for debugging and its behavior may change with a
new release. All flags are or-ed and may be given in C syntax (e.g. 0x0042) or as a comma
separated list of flag names. To get a list of all supported flags the single word "help" can be
used.

--debug-all
Same as --debug=0xffffffff

--tls-debug level
Enable debugging of the TLS layer at level. The details of the debug level depend on the used TLS
library and are not set in stone.

--debug-wait n
When running in server mode, wait n seconds before entering the actual processing loop and print
the pid. This gives time to attach a debugger.

--disable-check-own-socket
On some platforms dirmngr is able to detect the removal of its socket file and shutdown itself.
This option disable this self-test for debugging purposes.

-s
--sh
-c
--csh Format the info output in daemon mode for use with the standard Bourne shell respective the C-
shell. The default is to guess it based on the environment variable SHELL which is in almost all
cases sufficient.

--force
Enabling this option forces loading of expired CRLs; this is only useful for debugging.

--use-tor
--no-use-tor
The option --use-tor switches Dirmngr and thus GnuPG into ``Tor mode'' to route all network access
via Tor (an anonymity network). Certain other features are disabled in this mode. The effect of
--use-tor cannot be overridden by any other command or even by reloading dirmngr. The use of
--no-use-tor disables the use of Tor. The default is to use Tor if it is available on startup or
after reloading dirmngr.

--standard-resolver
This option forces the use of the system's standard DNS resolver code. This is mainly used for
debugging. Note that on Windows a standard resolver is not used and all DNS access will return
the error ``Not Implemented'' if this option is used. Using this together with enabled Tor mode
returns the error ``Not Enabled''.

--recursive-resolver
When possible use a recursive resolver instead of a stub resolver.

--resolver-timeout n
Set the timeout for the DNS resolver to N seconds. The default are 30 seconds.

--connect-timeout n

--connect-quick-timeout n
Set the timeout for HTTP and generic TCP connection attempts to N seconds. The value set with the
quick variant is used when the --quick option has been given to certain Assuan commands. The
quick value is capped at the value of the regular connect timeout. The default values are 15 and
2 seconds. Note that the timeout values are for each connection attempt; the connection code will
attempt to connect all addresses listed for a server.

--listen-backlog n
Set the size of the queue for pending connections. The default is 64.

--allow-version-check
Allow Dirmngr to connect to https://versions.gnupg.org to get the list of current software
versions. On debian-packaged versions, this option does nothing since software updates should be
handled by the distribution. See the option --query-swdb of the command gpgconf for more details.
Note, that regardless of this option a version check can always be triggered using this command:

gpg-connect-agent --dirmngr 'loadswdb --force' /bye

--keyserver name
Use name as your keyserver. This is the server that gpg communicates with to receive keys, send
keys, and search for keys. The format of the name is a URI: `scheme:[//]keyservername[:port]' The
scheme is the type of keyserver: "hkp" for the HTTP (or compatible) keyservers, "ldap" for the
LDAP keyservers, or "mailto" for the Graff email keyserver. Note that your particular installation
of GnuPG may have other keyserver types available as well. Keyserver schemes are case-insensitive.
After the keyserver name, optional keyserver configuration options may be provided. These are the
same as the --keyserver-options of gpg, but apply only to this particular keyserver.

Most keyservers synchronize with each other, so there is generally no need to send keys to more
than one server. The keyserver hkp://keys.gnupg.net uses round robin DNS to give a different
keyserver each time you use it.

If exactly two keyservers are configured and only one is a Tor hidden service (.onion), Dirmngr
selects the keyserver to use depending on whether Tor is locally running or not. The check for a
running Tor is done for each new connection.

If no keyserver is explicitly configured, dirmngr will use the built-in default of
hkps://keys.openpgp.org.

Note that the above default is a Debian-specific choice. Upstream GnuPG prefers
hkps://hkps.pool.sks-keyservers.net. See /usr/share/doc/gpgconf/NEWS.Debian.gz for more details.

Windows users with a keyserver running on their Active Directory should use ldap:/// for name to
access this directory.

For accessing anonymous LDAP keyservers name is in general just a ldaps://ldap.example.com. A
BaseDN parameter should never be specified. If authentication is required the value of name is
for example:

keyserver ldaps://ldap.example.com/????bindname=uid=USERNAME
%2Cou=GnuPG%20Users%2Cdc=example%2Cdc=com,password=PASSWORD

Put this all on one line without any spaces and keep the '%2C' as given.
Replace USERNAME, PASSWORD, and the 'dc' parts according to the
instructions received from the LDAP administrator. Note that only
simple authentication (i.e. cleartext passwords) is supported and thus
using ldaps is strongly suggested.

--nameserver ipaddr
In ``Tor mode'' Dirmngr uses a public resolver via Tor to resolve DNS names. If the default
public resolver, which is 8.8.8.8, shall not be used a different one can be given using this
option. Note that a numerical IP address must be given (IPv6 or IPv4) and that no error checking
is done for ipaddr.

--disable-ipv4

--disable-ipv6
Disable the use of all IPv4 or IPv6 addresses.

--disable-ldap
Entirely disables the use of LDAP.

--disable-http
Entirely disables the use of HTTP.

--ignore-http-dp
When looking for the location of a CRL, the to be tested certificate usually contains so called
CRL Distribution Point (DP) entries which are URLs describing the way to access the CRL. The
first found DP entry is used. With this option all entries using the HTTP scheme are ignored when
looking for a suitable DP.

--ignore-ldap-dp
This is similar to --ignore-http-dp but ignores entries using the LDAP scheme. Both options may
be combined resulting in ignoring DPs entirely.

--ignore-ocsp-service-url
Ignore all OCSP URLs contained in the certificate. The effect is to force the use of the default
responder.

--honor-http-proxy
If the environment variable ‘http_proxy’ has been set, use its value to access HTTP servers.

--http-proxy host[:port]
Use host and port to access HTTP servers. The use of this option overrides the environment
variable ‘http_proxy’ regardless whether --honor-http-proxy has been set.

--ldap-proxy host[:port]
Use host and port to connect to LDAP servers. If port is omitted, port 389 (standard LDAP port)
is used. This overrides any specified host and port part in a LDAP URL and will also be used if
host and port have been omitted from the URL.

--only-ldap-proxy
Never use anything else but the LDAP "proxy" as configured with --ldap-proxy. Usually dirmngr
tries to use other configured LDAP server if the connection using the "proxy" failed.

--ldapserverlist-file file
Read the list of LDAP servers to consult for CRLs and certificates from file instead of the
default per-user ldap server list file. The default value for file is ‘dirmngr_ldapservers.conf’.

This server list file contains one LDAP server per line in the format

hostname:port:username:password:base_dn

Lines starting with a ‘#’ are comments.

Note that as usual all strings entered are expected to be UTF-8 encoded. Obviously this will lead
to problems if the password has originally been encoded as Latin-1. There is no other solution
here than to put such a password in the binary encoding into the file (i.e. non-ascii characters
won't show up readable). ([The gpgconf tool might be helpful for frontends as it enables editing
this configuration file using percent-escaped strings.])

--ldaptimeout secs
Specify the number of seconds to wait for an LDAP query before timing out. The default are 15
seconds. 0 will never timeout.

--add-servers
This option makes dirmngr add any servers it discovers when validating certificates against CRLs
to the internal list of servers to consult for certificates and CRLs.

This option is useful when trying to validate a certificate that has a CRL distribution point that
points to a server that is not already listed in the ldapserverlist. Dirmngr will always go to
this server and try to download the CRL, but chances are high that the certificate used to sign
the CRL is located on the same server. So if dirmngr doesn't add that new server to list, it will
often not be able to verify the signature of the CRL unless the --add-servers option is used.

Note: The current version of dirmngr has this option disabled by default.

--allow-ocsp
This option enables OCSP support if requested by the client.

OCSP requests are rejected by default because they may violate the privacy of the user; for
example it is possible to track the time when a user is reading a mail.

--ocsp-responder url
Use url as the default OCSP Responder if the certificate does not contain information about an
assigned responder. Note, that --ocsp-signer must also be set to a valid certificate.

--ocsp-signer fpr|file
Use the certificate with the fingerprint fpr to check the responses of the default OCSP Responder.
Alternatively a filename can be given in which case the response is expected to be signed by one
of the certificates described in that file. Any argument which contains a slash, dot or tilde is
considered a filename. Usual filename expansion takes place: A tilde at the start followed by a
slash is replaced by the content of ‘HOME’, no slash at start describes a relative filename which
will be searched at the home directory. To make sure that the file is searched in the home
directory, either prepend the name with "./" or use a name which contains a dot.

If a response has been signed by a certificate described by these fingerprints no further check
upon the validity of this certificate is done.

The format of the FILE is a list of SHA-1 fingerprint, one per line with optional colons between
the bytes. Empty lines and lines prefix with a hash mark are ignored.

--ocsp-max-clock-skew n
The number of seconds a skew between the OCSP responder and them local clock is accepted. Default
is 600 (10 minutes).

--ocsp-max-period n
Seconds a response is at maximum considered valid after the time given in the thisUpdate field.
Default is 7776000 (90 days).

--ocsp-current-period n
The number of seconds an OCSP response is considered valid after the time given in the NEXT_UPDATE
datum. Default is 10800 (3 hours).

--max-replies n
Do not return more that n items in one query. The default is 10.

--ignore-cert-extension oid
Add oid to the list of ignored certificate extensions. The oid is expected to be in dotted
decimal form, like 2.5.29.3. This option may be used more than once. Critical flagged
certificate extensions matching one of the OIDs in the list are treated as if they are actually
handled and thus the certificate won't be rejected due to an unknown critical extension. Use this
option with care because extensions are usually flagged as critical for a reason.

--hkp-cacert file
Use the root certificates in file for verification of the TLS certificates used with hkps
(keyserver access over TLS). If the file is in PEM format a suffix of .pem is expected for file.
This option may be given multiple times to add more root certificates. Tilde expansion is
supported.

If no hkp-cacert directive is present, dirmngr will make a reasonable choice: if the keyserver in
question is the special pool hkps.pool.sks-keyservers.net, it will use the bundled root
certificate for that pool. Otherwise, it will use the system CAs.

EXAMPLES

       Here is an example on how to show dirmngr's internal table of OpenPGP keyserver addresses.  The output is
       intended for debugging purposes and not part of a defined API.

           gpg-connect-agent --dirmngr 'keyserver --hosttable' /bye

       To inhibit the use of a particular host you have noticed in one of the keyserver pools, you may use

          gpg-connect-agent --dirmngr 'keyserver --dead pgpkeys.bnd.de' /bye

       The description of the keyserver command can be printed using

          gpg-connect-agent --dirmngr 'help keyserver' /bye

FILES

Dirmngr makes use of several directories when running in daemon mode: There are a few configuration files
whih control the operation of dirmngr. By default they may all be found in the current home directory
(see: [option --homedir]).

dirmngr.conf
This is the standard configuration file read by dirmngr on startup. It may contain any valid long
option; the leading two dashes may not be entered and the option may not be abbreviated. This
file is also read after a SIGHUP however not all options will actually have an effect. This
default name may be changed on the command line (see: [option --options]). You should backup this
file.

/etc/gnupg/trusted-certs
This directory should be filled with certificates of Root CAs you are trusting in checking the
CRLs and signing OCSP Responses.

Usually these are the same certificates you use with the applications making use of dirmngr. It
is expected that each of these certificate files contain exactly one DER encoded certificate in a
file with the suffix ‘.crt’ or ‘.der’. dirmngr reads those certificates on startup and when given
a SIGHUP. Certificates which are not readable or do not make up a proper X.509 certificate are
ignored; see the log file for details.

Applications using dirmngr (e.g. gpgsm) can request these certificates to complete a trust chain
in the same way as with the extra-certs directory (see below).

Note that for OCSP responses the certificate specified using the option --ocsp-signer is always
considered valid to sign OCSP requests.

/etc/gnupg/extra-certs
This directory may contain extra certificates which are preloaded into the internal cache on
startup. Applications using dirmngr (e.g. gpgsm) can request cached certificates to complete a
trust chain. This is convenient in cases you have a couple intermediate CA certificates or
certificates usually used to sign OCSP responses. These certificates are first tried before going
out to the net to look for them. These certificates must also be DER encoded and suffixed with
‘.crt’ or ‘.der’.

~/.gnupg/crls.d
This directory is used to store cached CRLs. The ‘crls.d’ part will be created by dirmngr if it
does not exists but you need to make sure that the upper directory exists.

SIGNALS

       A running dirmngr may be controlled by signals, i.e. using the kill command  to  send  a  signal  to  the
       process.

       Here is a list of supported signals:

       SIGHUP This  signal  flushes  all  internally  cached  CRLs as well as any cached certificates.  Then the
              certificate cache is reinitialized as on startup.  Options  are  re-read  from  the  configuration
              file.  Instead of sending this signal it is better to use
         gpgconf --reload dirmngr

       SIGTERM
              Shuts  down  the  process  but waits until all current requests are fulfilled.  If the process has
              received 3 of these signals and requests are still pending, a shutdown is forced.   You  may  also
              use
         gpgconf --kill dirmngr
       instead of this signal

       SIGINT Shuts down the process immediately.

       SIGUSR1
              This prints some caching statistics to the log file.